Michael Phelps took the plunge in June, secretly marrying his longtime girlfriend two months before the Olympic great completed his last gold-medal haul.

The Arizona Republic reports the 31-year-old swimmer wedded Nicole Johnson on June 13. That’s a little more than a month after the former Miss California USA gave birth to their son, Boomer.

The newspaper has posted a copy of a marriage license that shows Phelps and Johnson were married in Paradise Valley, Arizona. Neither Phelps nor Johnson said anything about the wedding. Johnson posted a picture of her with Phelps and Boomer on Instagram on the day of the ceremony with the caption, "Such a memorable night with my lil fambam."

Phelps won five gold medals at the Rio de Janeiro Games, his last coming Aug. 13 to increase his overall total to 23.